Justin Bieber's tour bus busted for drugs

Justin Bieber's tour bus was stopped and seized for drugs on the North American leg of his Believe concert tour.

The 19-year-old played in Toronto, Canada on July 26, with his next dates taking place in the US cities of Detroit, Michigan and Newark, New Jersey.

According to TMZ, a "bus associated with Justin Bieber's tour was stopped" at Ambassador Bridge, which connects Windsor, Canada to Detroit. After a drug-sniffing hound detected narcotics on board, the vehicle was searched and authorities discovered marijuana and drug paraphernalia.

Bieber wasn't on the bus at the time and has not been charged with any crime in association with this drug discovery.

The bus driver was issued a citation and the rest of the passengers were released without incident.

This isn't the first time Bieber's tour vehicle has been suspected of housing drugs in 2013.

Swedish police reportedly searched Bieber's bus in Stockholm in April on suspicion that there was marijuana on board. Officers allegedly uncovered a "small amount" of the illegal drug in the vehicle, along with a stun gun - which requires a permit.

Bieber's Believe tour has been plagued by other bizarre events.

The singer's May 13 concert in Johannesburg, South Africa was raided by thieves.

After performing at the Soccer City stadium, a gang of marauders broke into a strongroom, according to BBC News.

The thieves were reportedly armed with ropes, hammers and chisels and made off with more than one million rand ($A111,000).

The cash included stadium earnings from Bieber's concert as well as from a previous show by Bon Jovi.